INDIANAPOLIS -- The final significant days of the offseason for the Indianapolis Colts (outside of when commissioner Roger Goodell disciplines owner Jim Irsay) starts Tuesday at the team's facility when they begin the first of three days of mandatory minicamp before breaking up for the final time prior to reporting for training camp July 23.

Let's take a look at several things to pay attention to during the camp:

The competition at running back, including Trent Richardson, won't be decided in this week's mandatory minicamp. Brian Spurlock/USA TODAY Sports

Offensive line battle: You can go ahead and put Khaled Holmes down as the starting center, but with Donald Thomas (quad, bicep) still working his way back, the starting guard positions could end up taking some time. Hugh Thornton, who took Thomas's spot after he was injured last season, has been working with the first team at right guard during organized team activities. Lance Louis had been working with the first team at left guard, but rookie Jack Mewhort, the Colts' second-round pick, moved ahead of him last week. The competition will intensify during training camp.

Running back competition: Just like the battle for the starting guard position, we won't get full competition for the starting running back position because Vick Ballard (knee) isn't expected to take part, as he's still working his way back from ACL surgery. Trent Richardson and Ahmad Bradshaw, the other two primary candidates, both wore red non-contact jerseys during OTAs. So this is another competition that won't pick up until training camp. All three players will get playing time, but keep in mind that coach Chuck Pagano said earlier in the offseason they want a workhorse in the backfield.

Landry sighting: Safety LaRon Landry has been the most significant healthy player missing during OTAs. It's not required for players to attend OTAs and Landry prefers to work out on his own during the offseason. But it still would have been good if he would have popped in for some of the workouts because of the need for improvement for the defense, the transition from a seasoned veteran in Antoine Bethea to possibly Delano Howell, who lacks significant experience, and Landry simply didn't have a great first season with the Colts. The offense, as long as Andrew Luck is the quarterback, will be fine. He's shown he can be effective even without good blocking. The same can't be said about a defense that finished 20th in the league last season.

The Bjoern factor: The fact linebacker Robert Mathis (suspension) won't be with the Colts the first four games of the season has definitely sunk in. Now it's up to second-year player Bjoern Werner, who gets the first shot to start in Mathis's absence, to prove he was worth the Colts selecting him in the first round after an inconsistent rookie season. "This year it's just knowing the defense and to feel comfortable in the defense," Colts defensive coordinator Greg Manusky said. "Now it's just his ability to get to the passer, which it's kind of you want him to do that in these OTAs, but he's never really going to get there because you don't have the pads on. But he's been doing a great job at least from the calls and signals and getting everything lined up and knowing exactly what he's supposed to do. It's a great situation for him."

Can Adams help: The Colts signed veteran safety Mike Adams over the weekend to take Corey Lynch's spot on the roster after placing him on injured reserve. Howell is leading the race to start, but Adams has started 73 games in his career. The question about Adams is: Does he have enough left in his 33-year-old body to help the Colts and possibly supplant Howell as the starting safety alongside Landry?

Who won't be there: Barring a sudden change of events, here are the players -- not including those on injured reserve -- you won't see taking part in minicamp. Receiver Reggie Wayne (knee), Ballard (knee) and Thomas (quad, bicep).